Abstract

A 2 years and 11 months old Belgian draught horse stallion with a membranous ventricular septal defect, severe aortic regurgitation, mild left ventricular enlargement and ventricular premature depolarisations was anaesthetised to perform open castration. A balanced anaesthetic approach, involving intravenous use of romifidine (80 µg/kg), morphine (0.1 mg/kg) and lidocaine (1 mg/kg) for premedication, followed by induction of anaesthesia with ketamine (2.2 mg/kg) and midazolam (0.06 mg/kg) and maintenance with isoflurane, lidocaine CRI (50 µg/kg/min) and intratesticular lidocaine 2 per cent (10 ml in each testicle) was used to optimise the cardiovascular stability and enhance the safety of the procedure. A multimodal analgesic approach was provided, aiming to reduce the amount of isoflurane required to maintain a surgical plane of anaesthesia. A smooth and uneventful recovery was obtained. The present case report describes an anaesthetic protocol that could be applied in similar cases.